1. Field of the Invention This invention relates to a conversational type programming apparatus which originates a numerical control (NC) tape for a numerically controlled (NC) machine tool or the like.
2. Description of the Related Art
Automatic programming for originating an ordinary NC tape utilizes an electronic computer to enter a tool path and other machining conditions on an NC tape based on a design drawing. In order to shorten the time from origination of a part program to completion of the NC tape and reduce programming errors, various conversational-type automatic programming apparatus having a CRT or other display function have been developed.
According to the process through which NC statements are generated by a conversational-type automatic programming apparatus, system data conforming to the type of machine tool is read in from a magnetic tape cassette, and use is made of a variety of data files stored at such time. More specifically, an operator causes a CRT to display various conversational-type data read and written while referring to a file, and originates a part program while observing the display. Meanwhile, processing is executed by the programming apparatus each time one line of the part program is entered. This is stored in memory as an NC program step.
In a case where a C-axis machining step is created for performing predetermined machining such as drilling a hole in the end face of a workpiece with the conversational automatic programming apparatus of the above type, the conventional practice is to define a C-axis profile which perpendicularly intersects the Z axis of the blank profile on a blank profile display screen. Next, a cursor is moved to a predetermined region of the defined C-axis profile and the particulars of a predetermined machining operation are selected. Whereupon the color in which the region corresponding thereto is displayed temporarily changes, informing the operator of the fact that the part program has been created.
The data file utilized in this case is formed as a separate data file depending upon the type of machining, such as counter-boring, drilling and tapping, even if the C-axis machining is the same. Accordingly, since the displayed color of the predetermined region of the blank temporarily changes at the moment one machining definition procedure from among the definition procedures ends, the operator can readily determine, on a region-by-region basis, whether a machining step regarding a machining type specified for each region has already been created.
However, with regard to origination of a machining program in which a C-axis profile is defined by a plurality of machining types, if machining which will not cause a change in the blank profile itself is selected, the displayed color indicating the region for which machining has been completed will vanish each time the data file is updated, and the color of the display will return to that of the original blank profile. As a result, the machining step will no longer be visually distinguishable. Furthermore, when a C-axis profile defined with regard to the same blank extends over a plurality of locations, the data files are read out in succession and it is particularly difficult to specify a region of the blank that is to be machined based thereon. In other words, with regard to situations in which only the displayed color of a profile temporarily changes without an accompanying change in the profile on the display screen, as in the case of counter-boring, drilling and tapping, it becomes difficult for the operator to understand the display when a program is created.